Field of the Invention
This invention generally relates to a communication device and a feeder device.
Background Information
Generally, an RFID (radio frequency identification) has been used to send and receive information by short-range wireless communication.
RFID tags are used for the RFID (hereinafter, an “RFID tag” will also be referred to as an “RF tag” or a “wireless device”). RFID tags have individual identification information in an internal memory, and perform communication with an RFID reader that makes use of radio waves or electromagnetism (hereinafter, an “RFID reader” will also be referred to as an “RF reader” or a “communication device”).
RFID is used in a variety of fields, such as stock control and security management. Particularly in recent years, merchandise and service information, and URL information about merchandise and services, stored on RF tags are displayed a tablet terminal by communicating with the RF tag and the tablet terminal, which serves as an RF reader. When a tablet terminal acquires URL information, the web page at that URL can be opened with a browser, either automatically or after user authorization.
Large tablet terminals have debuted in recent years. The antenna used to communicate with the RF tag is usually disposed in an area on the rear face side, inside the tablet terminal. Therefore, in communication with an RF tag, the rear face of the tablet terminal is moved closer to the RF tag. However, it is difficult for the user to grasp the relation between the RF tag and the antenna on the rear face of the tablet terminal. This results in positional offset. Particularly if the tablet terminal is larger in size, there tends to be a great deal of positional offset between the antenna and the RF tag.
Patent Literature 1 (Japanese Unexamined Patent Application Publication No. 2010-130729) discloses a charging device that performs charging by receiving electrical power from a transmission device. The charging device includes four magnetic sensors. The coil magnetic flux (or magnetic force) generated from the transmission device is detected by these magnetic sensors, thereby determining the positional relation between the transmission device and the charging device. The user can be prompted to set the positional relation between the transmission device and the charging device to a positional relation that is suited to charging. Specifically, an arrow is displayed on the display component of the charging device based on the positional relation determined.